Abstract : This report documents recent developments in cartridge case coatings designed to prevent the occurrence of burn-through in 5.56mm aluminum cartridge cases. The research work performed determined the effectiveness and general feasibility of five materials: red grip core paste, polyimide varnish (DuPont), The National Aeronautic and Space Administration's (NASA) 45B3 intumescent coating, polysulfide sheeting, and RTV-734 (Dow Corning) used in combination with other materials. As a result of test firings conducted using the aforementioned materials, two formulations, the NASA intumescent coating and the polysulfide sheeting, internally applied, emerged as the most successful candidates. In light of the general efficiency demonstrated by these materials, it is concluded that an internally applied case coating material could prove to be most effective in the prevention of burn-through 5.56mm aluminum cartridge cases.